A preliminary investigation on microstructural characteristics of interfacial zone between cement and exploded wood fiber strand by using SEM-EDS

The hydration behavior and strength performance of cement mixed with exploded wood fiber strand (WFS) obtained by the water-vapor explosion process have been studied previously. In the current study, the microstructural characteristics of cement–exploded WFS interfacial zone were examined using scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDS). The Ca/Si ratios at the interfacial zones and the elemental compositions of hydration products deposited in the tracheid lumen were investigated. In addition, the morphological differences and compositional variations of hydration products that developed on the wood surfaces were examined. The results revealed that the Ca/Si ratios at the interfacial zones were strongly influenced by the mixture compositions, and that the elemental compositions of the hydration products that filled the tracheid lumen were significantly different from those of the cement paste in the mixtures. Differences in morphology and composition of hydration products at the wood surfaces were also observed to correspond to the different mixture compositions. These characteristics are considered to be directly related to the bond property, and thus, to the mechanical performance of WCM.

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